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Geologic summary of the surface & subsurface features at Mammoth Cave, Kentucky, USA. Filmed & composed by Tabatha Beaver and James St. John (both School of Earth Sciences, Ohio State University at Newark). Video photography done in October 2011. Some stills from old postcards & National Park Service publications. Other stills taken by James St. John from 2008 to 2011 in Mammoth Cave Ridge and adjacent Flint Ridge. Depicted features in this video include: - Historic Entrance to Mammoth Cave - Green River - Sinkhole Plain - giant canyon passages (Houchins Narrows, Audubon Avenue, Broadway Avenue, Main Cave, Sandstone Avenue, Kentucky Avenue/Grand Avenue) - breakout domes/breakdown domes (Rotunda Room) - phreatic tubular passages (Gothic Avenue, Black Snake Avenue, Pensacola Avenue, Great Relief Hall, Sparks Avenue, Cleaveland Avenue) - canyon passages (Boone Avenue) - keyhole passages (Winding Way/Fat Man

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